Blocked chest drainage tubes can cause dangerous retained blood complications, most notably, cardiac tamponade, which essentially smothers the heart. A major drawback to passive drainage systems is that clots quickly develop within the tubing, which prevent proper drainage. Critical care nurses are trained to manually manipulate and “strip” the tube by hand ever 15-30 minutes, but this method is time-consuming and largely ineffective, because several inches of the drainage tube are actually under the patient's skin. It also depends on the nurse remembering to do the required stripping and tube maintenance.
Previous work in this field (U.S. Pat. Nos. 7,854,728, 7,951,243, 8,246,752, 8,048,233 and 8,388,759) allude to the same general problem, but use a different methodology for active clearance. In the referenced invention, a wire catheter with angled, looped tip is advanced through the chest tube and use to “scrape” the inside of the chest tube. However, in practice this has been problematic for a variety of reasons. Particularly, the wire loop tends to allow clots to form on itself, and the clotted loop can itself block the drainage tube, as well as push clots into the chest cavity when advancing the catheter.